The colorectal endoscopic submucosal dissection (ESD) remains technically challenging, especially for older patients who frequently encounter complex chronic diseases and have a loose colon. However, only limited number of studies are available for the safety of ESD in older patients with especially large laterally spreading tumors. Therefore, in this retrospective study, we compared the outcomes of ESD for laterally spreading tumors (LST) ≥3cm(cm) in older patients to that in younger patients.